According to The Los Angeles Times, the Sheriff’s Department originally said 27-year-old Donnell Thompson of Compton was a second suspect in a July 28 carjacking.

At a news conference on Tuesday, the department described two separate incidents that led to the tragedy.

It all started when a suspect, Robert Alexander, who has a lengthy criminal record, allegedly carjacked the driver of a 2012 Honda Civic, authorities said.

Deputies pulled over the vehicle in Compton. At some point, Alexander fired a weapon at the deputies, who returned fire as he fled from the vehicle. They eventually captured him in a house where he forced his way in at gunpoint.

Meanwhile, not far away, a homeowner reported a man, who turned out to be Thompson, lying facedown in his front yard.

According to the authorities, Thompson fit the description of the carjacker. The deputy called in to say he found the carjacking suspect, who may have been shot in the exchange of gunfire.

“I could see why they were thinking, ‘Yeah, that was our guy,’” homicide Lt. John Corina said, according to The Times.

Thompson did not respond to commands. SWAT deputies joined the scene, and set off “flash-bang” explosives. Thompson, they said, remained unresponsive.

Eventually, he was roused, and the deputies said he rushed at them with a hand in his waistband. That’s when one of them shot Thompson dead.

“The result is that we have an unarmed individual, who had committed no crime, who once again has been the victim of a law enforcement homicide,” he stated at a Los Angeles County Board of Supervisors meeting on Tuesday, according to The Times.

Ed Obayashi, a legal advisor to law enforcement agencies, told The Times that Thompson’s innocence has no bearing on the shooting. What matters, he said, is the perception of the deputy who killed Thompson.

Nevertheless, Dunn has filed a federal civil rights claim against the county and plans also to file a lawsuit, the Huffington Post reports.

“We’ve done our own investigation and have not heard anything to suggest that Donnell Thompson was in any way acting in an aggressive manner or in any way demonstrating that he posed a threat to anyone,” Dunn told The Post.

Thompson’s family, according to The Times, stated that he was mentally disabled, functioning with the mental ability of a 16-year-old. They described him as shy and harmless.

Investigators said Thompson had no criminal record. A toxicology report on whether he consumed alcohol or drugs is pending.